NONSPECIFIC lONSPECIFIC chronic ulcerative colitis is generally regarded as both a clinical and pathologic entity. However, to define this entity precisely in terms acceptable to most gastroenterologists is quite difficult. So long as the etiology remains unknown and the pathogenesis unclear, observations by experienced physicians of the clincial and pathological changes in ulcerative colitis probably provide the most serviceable guide to its recognition. The present study has involved a histopathologic and cytologic analysis of sigmoidoscopic biopsies taken from individuals with colonic inflammations of varying type and duration, as well as from control cases without inflammation. Among these were a number of patients with ulcerative colitis in different stages of activity or quiescence, similar to those reported by others.1-7The pathologic data indicate that in the persistent inflammatory reaction of ulcerative colitis the leukocytic sequences ordinarily observed in acute and chronic inflammation are altered. Materials and Methods Biopsy specimens were